摘要

Precocity is a common phenomenon among farmed Chinese mitten crab Eriocheir sinensis that significantly affect culture productivity and profitability. This study compared the reproductive performance, offspring quality, proximate and fatty acid composition of pond-reared precocious and normal sexual matured females of E. sinensis. While the average gonado-somatic index (GSI) of the normal female crabs was significantly lower than that of the precocious crabs, fecundity, egg fertilization and hatching rate were significantly higher in the former. On the other hand, comparing various larval quality parameters measured with newly hatched larvae produced by the two types of females, only significant difference detected was dry weight with larvae produced by the normal females having significant higher dry weight. Biochemical analysis showed that eggs produced by precocious females contained a higher water content, but lower DHA, n-3 PUFA and n-3 HUFA contents than those produced by normal crabs and egg fertilization and hatching rates were, in general, correlated positively with the biochemical and fatty acid composition of the eggs. However, interestingly, such a correlation was not identified in newly hatched larvae. The results of hepatopancreas and ovarian proximate and fatty acid composition analysis suggested that lower reproductive performance of precocious females is likely related to the deficiencies in PUFA and general poorer nutrient conditions of these crabs. Statement of relevance: The Chinese mitten crab, Eriocheir sinensis, is currently farmed throughout China. Precocity, commonly accounts for 15-30% of cultured crab populations, is a major problem for E. sinensis aquaculture. The precocious crabs reach terminal moult at small sizes, hence have low market value. To date, it is unknown whether the precocious crabs are reproductive functional. This study confirmed that precocious E. sinensis could produce viable offspring, and subsequently compared reproductive performance and offspring quality between normal and precocious E. sinensis, providing useful information for aquaculture of the species.